Odorless and colorless and tasteless, nitrogen's most important job is keeping plants and animals alive. This gas is crucial to survival on Earth because it helps sustain the metabolic processes that transfer energy in cells possible. Plants at the bottom of the food chain help provide nitrogen for animals and humans who eat the plants.

Unlike humans, plants can make their own food through photosynthesis. This process requires chlorophyll, and nitrogen is one of chlorophyll's major components. In addition to nitrogen, plants need other nutrients that come from water and the soil. When soil doesn't have enough of these nutrients, people can add them to the soil using fertilizer. Plants can get some nitrogen from the air, but rainfall and water don't supply them with much. In addition to keeping plants alive, nitrogen helps them grow faster and remain healthy.

Proteins are essential to animal's life and nitrogen helps create proteins. In addition to eating plants to obtain nitrogen, animals obtain it from eating other animals. Because you are the top of the food chain, you can get your nitrogen by eating plants or animals. When an animal dies, nitrogen compounds in the body's proteins breaks down. Soil bacteria convert these compounds into ammonia which eventually turns back into a nitrogen compounds in the soil. This process forms a nitrogen cycle where plants help give animals nitrogen and animals return it to the plants.

Before 1772, people did not know that nitrogen existed. Daniel Rutherford, a physician, discovered it by removing carbon dioxide and oxygen from the air and observing that the remaining gas could not support life or combustion. If you convert nitrogen into a liquid, you'll see that it almost looks like water. Manufacturers use nitrogen to create ammonia, a gas that they can turn into nitrogen fertilizer. Ammonia is also important feed supplement and has uses in the plastic industry.

Excess nitrogen can cause Algae and aquatic plants to grow too rapidly. This growth may be good for those life forms, but it may cause problems for others. Excess growth can clog water intakes, deprive lakes of oxygen and reduce the diversity of plant and animal life in the water. Too much nitrogen can also cause problems in infants who ingest nitrates in drinking water. The U.S. Geological Survey notes that pregnant women and children in Eastern Europe drink bottled water in locations where groundwater nitrogen levels are high.